Alkyl sulfate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl ether acetate, a succinic acid surfactant or an amino acid surfactant is conventionally used as a primary surfactant for a hair cleansing composition. As well, incorporating a cationic polymer into a cleansing composition is known as a way to improve the finger combability through the hair during shampooing/rinsing.
Patent Document 1 discloses a hair cleansing composition comprising (A) a copolymer which has a cationic group and a crosslinked structure in a molecular thereof, and which also carries a feature such that its 0.5 wt. % hydrogel satisfies the following equations: 0.3≦η1≦20 (Pa·sec), 0.01≦η2≦5 (Pa·sec), and η1>η2, wherein η1 means a viscosity at a shear rate of 1 sec−1 and η2 means a viscosity at a shear rate of 10 sec−1, each at 25° C., and (B) an anionic surfactant. According to its disclosure, the composition is nice to the touch and excellent in spreadability during application, has a good foamability, is superior in hair sensation during cleansing or after drying, and even more has a high conditioning effect after cleansing.
Patent Document 2 discloses a novel cleansing and conditioning composition containing (A) at least one sulfate or sulfonate anionic surfactant, (B) at least one carboxylic acid anionic surfactant other than the surfactant described in (A) and selected from polyoxyalkylenated (C6-C24) alkyl ether carboxylic acids, polyoxyalkylenated (C6-C24) alkyl aryl ether carboxylic acids or salts thereof, and polyoxyalkylenated (C6-C24) alkylamido ether carboxylic acids or salts thereof, (C) at least one amphoteric surfactant, and (D) at least one water-insoluble carboxylic ester.
Patent Document 3 discloses a cleansing composition containing the following three ingredients (A), (B) and (C): (A) an ether carboxylic acid surfactant represented by the formula (1), (B) a glyceryl ether having an alkyl or alkenyl group with from 4 to 12 carbon atoms, and (C) a cationic-group containing copolymer. The composition is described to be less irritating to the skin, has excellent foamability and foam quality, and provide a good sensation during cleansing and rinsing and after drying.
However, even such cleansing compositions taking advantage of the conventional technologies are still not enough to satisfy both of the foam performance and function needed for a hair cleansing composition simultaneously.    Patent Document 1: JP-A-2000-144184    Patent Document 2: JP-A-2006-282662    Patent Document 3: JP-A-2005-336387